There does seem to be something lacking. I love the creative freedom but it needs something to give it a little more depth, not sure what though. Maybe random quests within the game?? that would require some kind of story and a way to trigger them..hmm. Random invasions from the nether might be fun, would give you a reason to build that awesome fort and stock up on weapons.

If you stopped at building houses, you're not playing right. Minecraft is really all about building obscenely huge, wondrous creations.But admittedly, it's WAY more fun if you or your friends set up a server and all play together.